Andrew Breitbart, the outspoken conservative journalist, died Wednesday night in Los Angeles. He was 43.

Joel Pollak, the editor of Breitbart's Big Journalism website, confirmed the news, which was first posted on Big Journalism. Pollak wrote that Breitbart died of natural causes, and the Associated Press reported that he collapsed while out on a walk.

"We have lost a husband, a father, a son, a brother, a dear friend, a patriot and a happy warrior," the post read. "Andrew lived boldly, so that we more timid souls would dare to live freely and fully, and fight for the fragile liberty he showed us how to love."

Breitbart, a Los Angeles native and Tulane graduate, became one of the more recognizable conservative figures in the media world. He was a regular on Fox News and other news channels, a fixture at Tea Party events and an Internet entrepreneur.

He then founded Breitbart.com in 2005 and later launched BigHollywood.com, BigGovernment.com, BigJournalism.com and other sties. They mixed right-leaning commentary with aggregation of other stories and original reporting.

He uncovered or inserted himself into a series of major political stories over the past few years, including the Anthony Weiner scandal and the unwarranted firing of Agriculture Department official Shirley Sherrod.

"He loved nothing more than to be in the middle of it," Sean Hannity said Thursday on Fox News.

In the case of Weiner, Breitbart broke the news that the New York congressman was sending lewd photos to women. That eventually led to Weiner's resignation.

In the case of Sherrod, Breitbart posted videos that appeared to show Sherrod, an employee at the Department of Agriculture, making racist remarks. That led to her dismissal. Yet after the full video aired, it became clear that Breitbart edited the clips, prompting Sherrod to sue for defamation.

Breitbart was combative to the end. Just hours before his death, he argued over his Twitter account about the antics of conservative activist James O'Keefe, who has posted recordings embarrassing ACORN employees and NPR executives. Breitbart made a deal with O'Keefe to post O'Keefe's videos on his site.

Both Breitbart and O'Keefe relished taking on the mainstream media, big government and left-wing politicians.

"He does not pretend to be an expert in policy, or to be particularly interested in it. 'Just because I am paying attention to politics and culture doesn’t mean that I should be talking about the health-care bill, talking about the minutiae,' he told me. Instead, Breitbart is obsessed with wresting control of the political narrative from the established media organizations."

Breitbart was born Feb. 1, 1969, in Los Angeles and adopted by Gerald and Arlene Breitbart. Breitbart told Mead that his parents were a "quietly conservative" family, and that he was "reflexively liberal."

However, after a summer of school at American University and the Clarence Thomas Supreme Court hearings, he began to evolve into the vocal and rebellious conservative he was when he died.

"Breitbart charts his ideological odyssey as a visceral reaction against the rich-liberal entitlement and political correctness he encountered from West L.A. to Washington, D.C.," Lloyd Grove wrote in a profile for The Daily Beast in February 2010.

After graduating from Tulane, he bounced around in the film industry and at E!, working for the company's website.

"Andrew's image in the last few years unfortunately belied his real personality," said Lew Harris, Managing Editor of TheWrap and editor in chief of E! Online when Breitbart worked there. "Despite our polar opposite political beliefs, I always found him to be warm and personally charming and, of course, very passionate in his beliefs. Those of us who knew him will miss him."

Breitbart soon grew fascinated with the Drudge Report, the now iconic conservative website run by Matt Drudge. He worked as an editor there, and then later went on to work with Arianna Huffington as she was launching The Huffington Post.

Though those two sites sit on either side of the political spectrum, he was adamant that the media was biased toward the left, which helped inspire the sites he founded.

He was willing to verbally spar with anyone, a combative style that made him beloved by some and despised by others.

"He was fun personified," Greg Gutfeld, a friend and Fox News host, said on the network Thursday morning. "Even people who couldn’t stand him had to admit it."